fabiotacke/ringsig

The library implements a ring signature scheme in Swift. The algorithm is based on "How to leak a secret" (2001) by Rivest et al.

Installation

Swift Package Manager

.Package(url: "https://github.com/FabioTacke/RingSig.git", majorVersion: 1)

CocoaPods

pod 'RingSig', '~> 1.0'

Usage

import RingSig

// Generate the signer's RSA keypair
let signerKeyPair = RSA.generateKeyPair()
    
// Generate keypairs for the other participants in the ring signature scheme (i.e. the non-signers)
let nonSignerKeyPairs = [RSA.generateKeyPair(), RSA.generateKeyPair(), RSA.generateKeyPair()]
let nonSignersPublicKeys = nonSignerKeyPairs.map { $0.publicKey }
    
// The message to be signed
let message = "Hello, World!"
    
// Sign the message
let signature = RingSig.ringSign(message: message.data(using: .utf8)!, nonSignersPublicKeys: nonSignersPublicKeys, signerKeyPair: signerKeyPair)
    
// Everybody can now verify that the message was signed by someone of those whose public keys were included in the signature. Still the verifier is not able to tell who of them is the actual signer.
let verified = RingSig.ringSigVerify(message: message.data(using: .utf8)!, signature: signature)
assert(verified)

Disclaimer

The library uses a very basic RSA implementation and therefore shouldn't be considered to offer high crypto security. Furthermore performance was not a design goal when creating the library.

Package Metadata

Repository: fabiotacke/ringsig

Default branch: master

README: README.md